1. Field of the Invention
The present invention relates to implant systems and methods of forming and inserting a fiber. More particularly, the present invention relates to systems and methods for mixing a liquid including polysaccharide and a liquid including a cross linking agent to form a cross linked polysaccharide fiber.
2. Description of Related Art
Alginate is a polysaccharide material derived from brown seaweed. Although the predominate use of alginates is as a food additive to thicken and stabilize solutions, they are also used in various medical applications. Alginate can be easily cross linked into biocompatible hydrogels used as a cell immobilization matrix for various biotechnology applications. In addition, this substance can be used as a biodegradable gel/film coating in pharmaceutical applications. Alginate is also used to make wound dressings and pads capable of absorbing wound exudate and providing a moisture permeable wound covering.
By coming in contact with different ionic substances having certain affinities, alginate and other polysaccharides can exist in either a liquid or solid phase. In addition, alginates and other polysaccharides are capable of being reversibly cross linked so that they can either degrade or cross link on demand. The present invention relies on the ability of these materials to cross link on demand.
The inventors have discovered that alginate and other polysaccharides are particularly useful materials for forming a biocompatible implant. In addition, the inventors have discovered that implants formed of these materials are particularly useful in the treatment of intracranial aneurysms.
Intracranial aneurysms are extremely difficult to treat because they are often formed in remote cerebral blood vessels, which are very difficult to access. If left untreated, hemodynamic forces of normal pulsatile blood flow can rupture fragile tissue in the area of the aneurysm causing a stroke. In one type of treatment, coils are implanted in the body of a patient in an attempt to occlude blood flow to the aneurysm. However, this procedure is time consuming because it often requires bi-plane X-rays after placement of each coil. In addition, a procedurist normally needs to determine and select the proper size for the coils prior to implantation. Also, coils can compact over time because they fill approximately 40% of the aneurysm volume only.
In light of the foregoing, there is a need in the art for an improved implant and systems and methods for forming and implanting this implant.
Accordingly, the present invention is directed to systems and methods that substantially obviate one or more of the limitations of the related art. To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention includes an implant system including a first reservoir containing a first liquid including polysaccharide, and a second reservoir containing a second liquid including an ionic cross linking agent. The system also includes a cannula including a first lumen in fluid communication with the first liquid in the first reservoir, a second lumen in fluid communication with the second liquid in the second reservoir, a distal end portion wherein the first and second lumens fluidly communicate with one another to mix the first and second liquids and thereby form a cross linked elongate fiber, and an opening in the distal end portion allowing passage of the cross linked fiber therethrough.
In another aspect, the present invention includes a method of forming an implant in a body. The method includes introducing a cannula into the body, the cannula including a first lumen, a second lumen, and an opening in a distal end portion of the cannula. The first liquid is passed through the first lumen, and the second liquid is passed through the second lumen. The method also includes mixing the first and second liquids in the cannula to form a flexible cross linked fiber, moving the fiber through the opening in the cannula, and contacting the fiber against body tissue to allow the fiber to bend and to form the implant in the body.
In another aspect, the invention includes a method of forming a fiber for an implant. The method comprises passing the first liquid through a tubular member placed in a reservoir containing the second liquid, and flowing the first liquid into the second liquid via an opening in a distal end portion of the tubular member. The polysaccharide and the ions of the cross linking agent then cross link to form an elongate fiber.
In an aspect of the invention, the polysaccharide of the first liquid includes alginate, and the cross linking agent of the second liquid includes calcium.
In an additional aspect, the system for inserting the fiber includes a spool having fiber wound thereon, a chamber containing the spool, the chamber having an interior, a first opening, and a second opening, and a syringe including a barrel in fluid communication with the first opening and a plunger movable in the barrel, movement of the plunger in the barrel pressurizing the interior of the chamber to deliver the fiber through the second opening.
In a further aspect, a cutter is provided on the cannula to sever a portion of the fiber passing through the lumen and opening of the cannula.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.